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101.
JP Bronowicki F Weber-Larivaille JP Gut M Doffo?l D Vetter 《Canadian Metallurgical Quarterly》1997,21(11):848-853
OBJECTIVES: The association of anti-HBs immunoglobulins and anti-HBV vaccine could increase the immunogenicity of the latter. The aim of this prospective randomized trial was to compare the immunogenicity of anti-HBs vaccination and serovaccination in alcoholic patients with cirrhosis. METHODS: Alcoholic patients with cirrhosis were randomized in 2 groups: a) Vaccination group: 3 i.m. injections of GenHevac B followed by one booster at month 9; b) Serovaccination group: same vaccination schedule followed by one i.m. injection of anti-HBs immunoglobulins (500 IU). RESULTS: Twenty-five patients (17 males and 8 females, mean age 56 years) were included in the study: 13 received a vaccination and 12 received a serovaccination. After 12 months, the seroconversion rates were 69% and 67% in vaccination and in serovaccination groups, respectively. The predictive factors of non responsiveness were as following: Child B cirrhosis, low number of CD8, a high CD4/CD8 rate, the existence of HLA DR7 antigen, and the absence of HLA DR1 antigen. CONCLUSION: In alcoholic patients with cirrhosis, serovaccination does not increase the immunogenicity of anti-HBs vaccination and should not be recommended. 相似文献
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Quantitative estimates of dust exposure in a diatomaceous earth (DE) mining and milling operation have been derived based on air sampling records for the period 1948-1988. A total of 6395 records was included in the analysis. Conversion of results obtained by particle counting, expressed as millions of particles per cubic feet (mppcf) of gravimetrically from a filter cassette and expressed as mg m-3 total, were converted to mg m-3 respirable dust using a conversion factor derived from data obtained during the same periods at the plant. Conversion factors were calculated as the average difference of means on the log scale in order to provide stable and consistent conversions and as a ratio of arithmetic means so that the results could be compared with similar studies. After converting the available data to mg m-3 respirable dust, geometric mean (geometric standard deviation) concentrations were 0.37 (2.43) during the 1950s and 0.17 (2.35) during later periods. Exposures were estimated using two linear models, one estimating the changes in concentration over time, and the other providing job-specific mean exposures during the more recent period. Extrapolation of the estimates to periods prior to the availability of any data was done using a subjectively-determined scaling factor. The average estimated respirable dust concentrations for 135 jobs were 3.55 (+/-1.25), 1.37 (+/-0.48), 0.47 (+/-0.16) and 0.29 (+/-0.10) mg m-3 prior to 1949, 1949-1953, 1954-1973 and 1974-1988, respectively. Despite the limitations of the available data, the estimation procedures used are expected to provide reasonable quantitative estimates of silica-containing dust exposure for subsequent exposure-response analyses. 相似文献
107.
Gerhard Vetter 《化学,工程师,技术》1985,57(3):218-229
Leakfree oscillating positive-displacement pumps – state of the art and trends of development . Leak- and maintenance-free oscillating positive-displacement pumps are very important for avoiding pollution and improving the reliability of plants. Technical progress in the field of hydraulic diaphragm- and tube-pumps for high pressures are explained. The actual data (pressure, efficiency, temperature) and experience with different fluids are surveyed. The various hydraulic control systems, the diaphragm design, and methods for rupture-control are compared. Further development trends are explained. 相似文献
108.
Vetter S.L. Hastie J.E. Korpijarvi V.-M. Puustinen J. Guina M. Okhotnikov O. Calvez S. Dawson M.D. 《Electronics letters》2008,44(18):1069-1070
The use of GaInNAs/GaAs as an alternative active material to InGaAs/GaAs for semiconductor disk lasers with Watt-level emission in the 1160?1210 nm wavelength range is reported. 相似文献
109.
D. Vetter 《e & i Elektrotechnik und Informationstechnik》2001,118(5):271-272
Ohne Zusammenfassung 相似文献
110.
Andreas Vetter Finn S. Babbe Bernhard Hofbeck Peter Kubis Michael Richter Stephan J. Heise Jrg Ohland Ingo Riedel Christoph J. Brabec 《Progress in Photovoltaics: Research and Applications》2016,24(7):1001-1008
Local electric defects may result in considerable performance losses in solar cells. Infrared (IR) thermography is one important tool to detect these defects on photovoltaic modules. Qualitative interpretation of IR images has been carried out successfully, but quantitative interpretation has been hampered by the lack of “calibration” defects. The aims of this study are to (i) establish methods to induce well‐defined electric defects in thin‐film solar cells serving as “calibration” defects and to (ii) assess the accuracy of IR imaging methods by using these artificially induced defects. This approach paves the way for improving quality control methods based on imaging in photovoltaic. We created ohmic defects (“shunts”) by using a focused ion beam and weak diodes (“interface shunts”) by applying a femto‐second laser at rather low power on copper indium gallium selenide cells. The defects can be induced precisely and reproducibly, and the severity of the defects on the electrical performance can be well adjusted by focused ion beam/laser parameters. The successive assessment of the IR measurement (ILIT‐Voc) revealed that this method can predict the losses in Pmpp (maximal power extractable) with a mean error of below 10%. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献